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Alternative fuel

Discussion in 'Alternative Energy' started by arrie, Jul 8, 2008.

  1. jpanhalt

    jpanhalt Well-Known Member Most Helpful Member

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    Where did you get that idea? Water is not an oxidizer. Pure mineral oil does not react with it at any discernible rate.

    John
     
  2. killivolt

    killivolt Well-Known Member

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    Nueltralizing acids in refrigeration systems


    The oil in refrigeration systems becomes corrupted when you have the presents of water maybe mixing with the refrigerant ? The Technicians have to neutralize it and replace the oil.

    http://www.qwik.com/PDFs/Discussion_of_Acid.pdf

    kv Thanks John.
     
  3. arrie

    arrie New Member

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    Turbine engines such as turbo-props makes use of the water trick as well. It cools the turbine, allowing a higher mass of fuel, hence higher power output.
    This trick is only utilised during take-off, otherwise all turbine-like engines has optimum efficiency at 89 to 90% throttle.

    And off coarse, the water is not pure either, mixed with methanol. Pilots always talk about water meth injection.

    That also influences the whole balance, but the end result is to cool the engine using evaporation.
    I also don't think the issue with acid and rust would be same with a turbine engine compared to anything else.
    For obvious reasons.
     
  4. dave

    Dave New Member

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  5. 3v0

    3v0 Coop Build Coordinator Forum Supporter

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    An IC engine produces water as a byproduct of combustion. That is why mufflers rust out.
     
  6. arrie

    arrie New Member

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    3v0, you're absolutely right.
    Take note though, unleaded does not have a rusting effect on silencers.
    I remember back in the day, not that long ago, of leaded petrol here in South Africa, man you were lucky to get two years from a silencer.
    Since driving my last three cars, all Fords, on unleaded, I've never replaced a silencer.
    And never used a stainless silencer or exhaust system ever.
    Now that has been more that 320 000 km, without replacing a silencer or fixing it.
    Yet unleaded fuel that has burned also produces water.
     
  7. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I would completely disagree, silencers rust just as much on unleaded as leaded, I've found no difference at all over all the years the UK has been lead free. I've just had the rear section of my exhaust system replaced for the second time, this on a car that's just over 5 years old - cause, rusted through from the inside, just as they always fail.
     
  8. jpanhalt

    jpanhalt Well-Known Member Most Helpful Member

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    I didn't know it was mixed with methanol. Makes sense, as the alcohol would act as a wetting agent. The Leidenfrost effect actually slows the vaporization of water when it is put onto a very hot surface (like in a turbine). John
     
  9. 3v0

    3v0 Coop Build Coordinator Forum Supporter

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    Exhaust systems on cars with catalytic converters run hoter. But if trips are short they never get up to temp.

    I have always wondered if the alcahol was there to anything other then prevent the water from freezing. I found this on http://www.turbomirage.com/water.html

    "Water Injection, or water/alcohol injection, acts as a highly effective gaseous intercooler. The only reason for an intercooler is to cool down the hot, compressed air from the turbo. Water can do this job far better because it has a very high property of Latent Heat of Evaporation, 500+ BTUs compared to gasoline's 135 BTUs and alcohol's 470. If you need an extra bit of fuel, a 50-50 ratio of alcohol to water strikes a good balance between the maximum anti-knock capability of water and maximum supplemental fuel."​

    I have doubts about water only acting as an intercooler (I am not sure they are saying that). That would not do much to lower combustion temperatures. I think it is the water turing to steam in cylinder that does that.

    But they do say that the alcohol acts as a fuel.
     
  10. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I don't do any trips that short, the engine (and exhaust) gets to full temperature everytime I use it.
     
  11. arrie

    arrie New Member

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    Nigel,that is weird.
    I bought my Ford Ikon in 2002, so six years on, and I have not replaced an exhaust or even worked on it. As it is a budget vehicle, it is not fitted with stainless steel.
    Same on the car I had before that, 1996 Ford Escort, no SS, yet I drove it from 1999 to 2003, when I sold it, it had 229000km on the clock.
    Don't know if anyone ever noticed, the 1.6 Escort has this funny round box right after the engine, but it was clearly visible underneath the car, I once destroyed the front area of that box when out bundu-bashing with the car on some trip.
    Went to the nearest exhaust place, told them to cut it out and weld a normal piece of pipe in its place. That was probably during 2000 or 2001.
    That also never perished, nor the welds.
    The only explanation I could form for that was the unleaded fuel compared to my first leaded fuel vehicle which went through silencers at about the same rate as tires or batteries.
    Do you think UK's comparatively wet climate to our dry climate can be a factor Nigel?
    Something else of unleaded compared to leaded, your engine oil retained its oily colour for much longer compared to leaded fuel, where it goes dark almost after the first drive.

    3v0, it's the effect of evaporation causing the cooling, your right, we just called it water as that is the state it is stored in.
    I'm not sure why the methanol is added as turbine engines does not suffer from knock like IC engines, surely you would not require the extra fuel, jet-A1 already fulfils that requirement without the need to add alcohol.
    What pilots do say is that water-meth injections are a great way of having a visible increase in power for take-off. It is switched off after the craft is airborne, so is implemented for only a number of seconds.

    Oh, and none of my vehicles use cats, and I probably never will make use of a cat system. And I do quite a share of short trips with my Ikon, not the Mondeo so much.
     
    Last edited: Aug 3, 2008
  12. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Possibly?, but as you are already aware, unleaded petrol makes just the same water as leaded does - perhaps you've just been lucky?.

    Not an option in the UK, as far as I know all recent cars use cats, and they aren't roadworthy without them (yearly MOT tests check emissions, but only on three year old or more vehicles).
     
  13. arrie

    arrie New Member

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    I've also been lucky with batteries, seem to get quite a lot of years from them, 5+ years with my Ikon before failing.
    I've heard people talking that unleaded fumes are very toxic, but it could be nasty rumours. We've had reports of poor reliability and tremendous expense with cats so I stay clear. It's almost the very expensive and luxury vehicles here that is fitted standard with cats.
     
  14. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    As far as I'm aware it's far better than leaded exhaust.

    As for batteries, again you have a warm dry climate :D

    But mine's fine after 5+ years anyway, I can't say I've ever had any great problems with batteries?.

    It's going to come, there can't be many countries left where they aren't a legal requirement now - as far as I'm aware they are pretty reliable, and a LOT cheaper to replace than they used to be.

    If you're hearing about poor reliabilty, it's likely people are still using leaded fuel sometimes - use it once and it destroys the cat.
     
  15. arrie

    arrie New Member

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    We don't have leaded fuel any more, haven't had for some years now.
    We do have these so called dual fuels, or lead substitute fuels, since we still have quite a number of vehicles from the leaded era on our roads.

    So does cats reduce the amount of CO2 emissions?

    I would think that we are far from that law over here, maybe by that time some alternative that all manufacturers are claiming to be close will be with us already.
     
  16. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I'm not sure what it reduces, I think it might be CO2 - it's listed on my MOT certificate, but I can't say I paid any attention.
     
  17. arrie

    arrie New Member

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    I mean, if you only have water and CO2 after ignition, it must be that.

    Except if other toxins exist nobody is really telling us about. Which can bring us back to the rusting saga of earlier.

    But I'll have to research that.
     
  18. 3v0

    3v0 Coop Build Coordinator Forum Supporter

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    More along the line of carbon monoxide to carbon dioxide. Also reduces NOX and unburned fuel.


     
  19. arrie

    arrie New Member

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    Thanks 3v0.
    That is interesting.

    So my conclusion is that the IC engines are not as efficient in its combustion as they claim.
    Otherwise the cat would not be required.
     
  20. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I don't think anyone has ever claimed any great degree of efficiency for IC engines? - nor does it's specific waste products have any real bearing on it's efficiency, you could probably increase efficiency at the cost of making it's waste products worse.
     
  21. arrie

    arrie New Member

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    No really, most claim combustion efficiency of between 97 and 99%.
    I'm not nearly a microbiologist, but them mostly all you should get out is CO2 and H2O, right?
     

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